The invention described herein relates generally to X-ray lasers, and more particularly to laboratory X-ray lasers that provide laser radiation within the wavelength range between the K absorption edges of carbon and oxygen, and are thus especially suited for use in the microscopy of biological specimens.
The first operational laboratory X-ray laser is taught by Campbell and Rosen in U.S. Pat. No. 4,827,479 issued May 2, 1989. Moreover, this X-ray laser is also described by Rosen et al in Physical Review Letters 54, 106 (1985), with a discussion of the experimental demonstration of the laser provided by Matthews et al in Physical Review Letters 54, 110 (1985). This seminal work was also reported in Physics Today, March 1985, at pages 17 to 19.
A recent review of soft X-ray lasers is provided by Matthews and Rosen in Scientific American, December 1988, at pages 86 to 91. This article is incorporated by reference herein. At page 86, the article states that the X-ray lasers now in operation ". . . produce soft X-rays down to about five nanometers . . . ", that, is down to wavelengths as short as about 50 Angstroms. This is unfortunate, because an X-ray laser operating at significantly shorter wavelengths, between the K edge of carbon at 44 Angstroms and the K edge of oxygen at 23 Angstroms, would be ideal for the microscopy of biological specimens in terms of penetration, contrast, and resolution.